US6421541B1 - Adaptable bandwidth - Google Patents

Adaptable bandwidth Download PDF

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Publication number
US6421541B1
US6421541B1 US09/488,314 US48831400A US6421541B1 US 6421541 B1 US6421541 B1 US 6421541B1 US 48831400 A US48831400 A US 48831400A US 6421541 B1 US6421541 B1 US 6421541B1
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US
United States
Prior art keywords
bandwidth
central node
data rate
link
terminal
Prior art date
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Expired - Lifetime
Application number
US09/488,314
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English (en)
Inventor
Ingemar Folke Karlsson
Kent Olof Falk
Magnus Bonnedal
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Telefonaktiebolaget LM Ericsson AB
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Telefonaktiebolaget LM Ericsson AB
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Filing date
Publication date
Priority to SE9900195A priority Critical patent/SE515837C2/sv
Priority to PCT/SE2000/000076 priority patent/WO2000044110A1/en
Priority to AU23373/00A priority patent/AU2337300A/en
Application filed by Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Priority to US09/488,314 priority patent/US6421541B1/en
Assigned to TELEFONAKTIEBOLAGET L M ERICCSON reassignment TELEFONAKTIEBOLAGET L M ERICCSON ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BONNEDAL, MAGNUS, FALK, KENT OLOF, KARLSSON, INGEMAR FOLKE
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Publication of US6421541B1 publication Critical patent/US6421541B1/en
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W52/00Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04TPC
    • H04W52/18TPC being performed according to specific parameters
    • H04W52/26TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service]
    • H04W52/265TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service] taking into account the quality of service QoS
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00Arrangements for detecting or preventing errors in the information received
    • H04L1/0001Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0023Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
    • H04L1/0025Transmission of mode-switching indication
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W52/00Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04TPC
    • H04W52/18TPC being performed according to specific parameters
    • H04W52/26TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service]
    • H04W52/267TPC being performed according to specific parameters using transmission rate or quality of service QoS [Quality of Service] taking into account the information rate

Definitions

  • the present invention relates to a method for attenuation compensation in a communication system, and more exactly to a method to adapt the band-width as a result of signal attenuation.
  • a further problem is that many satellite systems are interference limited, which implies that the entire dynamic range for weather changes and eventual changes in distance between transmitter and receiver must be compensated by a regulation of the transmitter output power. Dynamically this leads to that the transmitter working point for certain cases must be changed by more than 20 dB.
  • JP 63-262924A discloses a device for satellite communication, in which a decision circuitry calculates the excess of a precipitation attenuation over the range of power control and then changes the data rate to satisfy the prescribed line quality.
  • Another document, JP 41-3044317A also contemplates a way to keep the actual quality of a satellite communication line constant at all times by measuring a BER (bit error rate) of a loop-backed pilot signal and adjust transmission speed of the pilot signal to maintain a preset bit error rate independent of the channel attenuation. The result of the pilot signal measurement is then controlling the transmission power.
  • BER bit error rate
  • Still another document JP 21-13653A describes a method to effectively utilize frequencies in a simple constitution, and to effectively make them to function for various types of fading by providing a large capacity transmitting system and a small capacity transmitting system.
  • the receiving condition is supervised by means of a receiving system, and a switching of transmitting systems between the transmitting side and receiving side takes place assisted by a switching control signal being the supervisory result.
  • the small capacity transmitting system utilizes a narrowed transmission bandwidth. However the regulation takes place only in two steps and requires the equipment to be doubled.
  • the present invention discloses a method in which the bandwidth is decreased instead of increasing EIRP in order maintain a same power density per Hz at the receiver in cases of poor weather conditions resulting for instance in precipitation attenuation or fading.
  • This also leads to a reduced data transmission rate for the specific channel due to the poor weather conditions, but different from the state of the art, the reduced bandwidth instead allows more subscribers to be connected.
  • the dynamics of the transmitter output power regulation will only need to cover the steps of bandwidth regulation. If the bandwidth is reduced, for instance, by dividing by a factor two it will be enough with an order of 3 dB dynamics or ⁇ 1.5 dB in the regulation of the transmitter output power.
  • FIG. 1 is a block diagram illustrating an embodiment, which utilizes the adaptable bandwidth concept according to the present invention.
  • FIG. 2 is a block diagram, which illustrates an up-link processor.
  • the adaptable bandwidth concept requires a closed loop system.
  • the terminal communicates with a central, which might be a satellite, a node in a multiple-point system or a base-station.
  • the central measures the received power level and supplies the terminal with instructions regarding which bandwidth and which part of the band it may use.
  • the central station also manages the portion of the frequency spectrum made free such that it may be used elsewhere in the system.
  • the system shall be designed to be so robust that it is sufficient to adapt the bandwidth in practical steps. It will even be possible to combine the adaptable bandwidth with a power tuning, but this makes the system more complex.
  • FIG. 1 is demonstrated a block diagram for an embodiment of a terminal utilising a possible implementation of the adaptable bandwidth concept. Except for the variable bandwidth feature the design is similar to terrestrial radio link apparatuses like LMDS (Local Multi-point Distribution System) and satellite terminal concepts.
  • LMDS Local Multi-point Distribution System
  • the terminal control and interface unit, CIU manages the function of the terminal.
  • the CIU is provided with a set of terminals, TRM, which are adapted to be connected to a number of peripheral devices such as external networks, a personal computer, a telephone, a multimedia system, a TV, etc.
  • the CIU comprises a central control unit CCU, a base-band processor BP, an up-link processor UP and a down-link processor DP.
  • the CCU manages the overall control of the terminal and steers the processors.
  • the base-band processor BP performs protocol adaptation, that is performing adaptations between the protocol for communication utilised by the system and the protocol or protocols utilised by the peripherals, for instance the IP protocol.
  • the CCU also controls the access, security codes, billing and control of power and bandwidth allocations by addressing data and steering to the different processors.
  • the up-link processor, UP presented in FIG. 2 contains data rate control DRC, buffers B, a modulator M, a D/A converter, a frequency synthesiser FS and an up-converter, UIF, to the intermediate frequency IF.
  • DRC data rate control
  • M modulator
  • D/A converter a frequency synthesiser
  • UIF up-converter
  • power tuning it can be implemented in a number of ways, for example as a fine level adjustment of the IF signal level. A small power tuning of the order ⁇ 1.5 dB will then be sufficient in combination with a control of the data rate in steps with the use of a base of two.
  • the down-link processor DP comprises for example frequency generator, base-band down-converter, A/D converter, demodulator, Viterbi decoder.
  • the up- and down-link processors are connected to a signal unit S (FIG. 1 ), which comprises an up-converter UC, a power amplifier HPA, a duplexer D, an antenna A, a low noise amplifier LNA and a down-converter DC.
  • An incoming high frequency signal from the antenna A goes through the duplexer D into the low noise amplifier LNA and is down-converted to IF frequency in the down-converter DC.
  • the IF-signal then goes to the down-link processor DP where the signal is converted to base-band and demodulated.
  • the data is then distributed to the proper terminal TRM by the central control unit CCU, which also reads administrative data, for example, information about bandwidth and power levels. Based on this information the data flow on the up-link is modified in the up-link processor UP.
  • the up-link IF signal is transmitted and up-converted to high frequency in the up-converter UC.
  • the signal is amplified in the power amplifier HPA and is passed through the duplexer D and then transmitted via the antenna A.
  • the inventive idea is generally applied for an up-link from a ground terminal to a communication satellite.
  • this communication an increased attenuation over the distance is compensated by a stepwise decreased bandwidth at a constant output power of the transmitter.
  • the solution results in that power received per unit bandwidth in the satellite may be kept constant and the transmission error rate will be unchanged. Bandwidth not taken by the specific channel may then be utilized by other terminals and the operator gains optimal working conditions and occupancy of the satellite, and consequently a better economical standpoint for the system operator.
  • the up-link is dimensioned for a nominal atmospheric attenuation and/or with little margin for other increased propagation loss. This will increase the system capacity during normal propagation conditions. As an example, a reduction of the margin with 10 dB, will during the time the margin is not required, increase the link capacity by roughly a factor 3.
  • the maximum available power of the up-link transmitter is concentrated to a bandwidth that is narrowed by the same factor as the increased link attenuation.
  • the link capacity is reduced by the same factor, but the signal to noise density including co channel interference will remain constant.
  • the frequency band liberated by the attenuated channel can hence be used for other channels for which the capacity is increased, or for additional channels.
  • the total system capacity will hence remain constant.
  • a second realization applies to CDMA systems.
  • the configuration is similar to the first realization, with the exception that the modulation is different, the local oscillator, LO is fixed and the output filter is always appropriate for the transmitted band.
  • the link attenuation is increased, the data rate is reduced and the CDMA coding is changed, so that a smaller fraction of the total band capacity is used by the link. This may in the present case best be contemplated as keeping the energy per data bit constant, hence keeping the signal density constant at the receiver location, i.e. the power per bit.
  • a combination of power tuning and variable data rate can be used. If the data rate and hence the CDMA coding is changed in steps by a factor of two, the output power tuning can be used to balance the power per bit at the receiver.

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  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Radio Relay Systems (AREA)
  • Mobile Radio Communication Systems (AREA)
US09/488,314 1999-01-22 2000-01-20 Adaptable bandwidth Expired - Lifetime US6421541B1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
SE9900195A SE515837C2 (sv) 1999-01-22 1999-01-22 Adapterbar bandbredd
PCT/SE2000/000076 WO2000044110A1 (en) 1999-01-22 2000-01-17 Adaptable bandwidth in a communication system
AU23373/00A AU2337300A (en) 1999-01-22 2000-01-17 Adaptable bandwidth in a communication system
US09/488,314 US6421541B1 (en) 1999-01-22 2000-01-20 Adaptable bandwidth

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9900195A SE515837C2 (sv) 1999-01-22 1999-01-22 Adapterbar bandbredd
US09/488,314 US6421541B1 (en) 1999-01-22 2000-01-20 Adaptable bandwidth

Publications (1)

Publication Number Publication Date
US6421541B1 true US6421541B1 (en) 2002-07-16

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US09/488,314 Expired - Lifetime US6421541B1 (en) 1999-01-22 2000-01-20 Adaptable bandwidth

Country Status (4)

Country Link
US (1) US6421541B1 (sv)
AU (1) AU2337300A (sv)
SE (1) SE515837C2 (sv)
WO (1) WO2000044110A1 (sv)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020110101A1 (en) * 2000-12-06 2002-08-15 Nandu Gopalakrishnan Method for data rate selection in a wireless communication system
US20050195746A1 (en) * 2004-03-05 2005-09-08 Eugene Golovinsky Method of heuristic determination of network interface transmission mode and apparatus implementing such method
US20070173260A1 (en) * 2006-01-23 2007-07-26 Love Robert T Wireless communication network scheduling
US20080025254A1 (en) * 2006-07-25 2008-01-31 Motorola Inc Spectrum emission level variation in schedulable wireless communication terminal
US20090193137A1 (en) * 1995-07-14 2009-07-30 Broadband Royalty Corporation Dynamic quality adjustment based on changing streaming constraints
US20120129448A1 (en) * 2010-11-19 2012-05-24 The Boeing Company Repeater design and verification tool
US8463314B2 (en) 2006-01-23 2013-06-11 Motorola Mobility Llc Power control in schedulable wireless communication terminal
US9565655B2 (en) 2011-04-13 2017-02-07 Google Technology Holdings LLC Method and apparatus to detect the transmission bandwidth configuration of a channel in connection with reducing interference between channels in wireless communication systems
US9622190B2 (en) 2006-07-25 2017-04-11 Google Technology Holdings LLC Spectrum emission level variation in schedulable wireless communication terminal
US20180091866A1 (en) * 2016-09-23 2018-03-29 Verizon Patent And Licensing Inc. Methods and Systems for Concurrently Transmitting Object Data by Way of Parallel Network Interfaces
US10064132B2 (en) * 2015-08-19 2018-08-28 Diehl Metering Systems Gmbh Bidirectional wireless data transmission method
CN114204976A (zh) * 2021-11-30 2022-03-18 中国卫通集团股份有限公司 一种通信终端及通信方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB0029002D0 (en) * 2000-11-28 2001-01-10 Nokia Networks Oy Channels in a communication system
US6944460B2 (en) 2001-06-07 2005-09-13 Telefonaktiebolaget L M Ericsson (Publ) System and method for link adaptation in communication systems
EP1309105A1 (de) * 2001-11-01 2003-05-07 Ascom Systec AG Satelliten/Zellular zwei Betriebsart Endgerät

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Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9832244B2 (en) * 1995-07-14 2017-11-28 Arris Enterprises Llc Dynamic quality adjustment based on changing streaming constraints
US20090193137A1 (en) * 1995-07-14 2009-07-30 Broadband Royalty Corporation Dynamic quality adjustment based on changing streaming constraints
US6930981B2 (en) * 2000-12-06 2005-08-16 Lucent Technologies Inc. Method for data rate selection in a wireless communication system
US20020110101A1 (en) * 2000-12-06 2002-08-15 Nandu Gopalakrishnan Method for data rate selection in a wireless communication system
US7742423B2 (en) * 2004-03-05 2010-06-22 Bmc Software, Inc. Method of heuristic determination of network interface transmission mode and apparatus implementing such method
US20100220625A1 (en) * 2004-03-05 2010-09-02 Bmc Software, Inc. Heuristic Determination of Network Interface Transmission Mode
US7940691B2 (en) 2004-03-05 2011-05-10 Bmc Software, Inc. Heuristic determination of network interface transmission mode
US20050195746A1 (en) * 2004-03-05 2005-09-08 Eugene Golovinsky Method of heuristic determination of network interface transmission mode and apparatus implementing such method
US8463314B2 (en) 2006-01-23 2013-06-11 Motorola Mobility Llc Power control in schedulable wireless communication terminal
US8478328B2 (en) 2006-01-23 2013-07-02 Motorola Mobility Llc Power control in schedulable wireless communication terminal
US20070173260A1 (en) * 2006-01-23 2007-07-26 Love Robert T Wireless communication network scheduling
US20080025254A1 (en) * 2006-07-25 2008-01-31 Motorola Inc Spectrum emission level variation in schedulable wireless communication terminal
US9622190B2 (en) 2006-07-25 2017-04-11 Google Technology Holdings LLC Spectrum emission level variation in schedulable wireless communication terminal
US20120129448A1 (en) * 2010-11-19 2012-05-24 The Boeing Company Repeater design and verification tool
US8725068B2 (en) * 2010-11-19 2014-05-13 The Boeing Company Repeater design and verification tool
US9565655B2 (en) 2011-04-13 2017-02-07 Google Technology Holdings LLC Method and apparatus to detect the transmission bandwidth configuration of a channel in connection with reducing interference between channels in wireless communication systems
US10064132B2 (en) * 2015-08-19 2018-08-28 Diehl Metering Systems Gmbh Bidirectional wireless data transmission method
US20180091866A1 (en) * 2016-09-23 2018-03-29 Verizon Patent And Licensing Inc. Methods and Systems for Concurrently Transmitting Object Data by Way of Parallel Network Interfaces
US10560755B2 (en) * 2016-09-23 2020-02-11 Verizon Patent And Licensing Inc. Methods and systems for concurrently transmitting object data by way of parallel network interfaces
CN114204976A (zh) * 2021-11-30 2022-03-18 中国卫通集团股份有限公司 一种通信终端及通信方法
CN114204976B (zh) * 2021-11-30 2024-03-19 中国卫通集团股份有限公司 一种通信终端及通信方法

Also Published As

Publication number Publication date
WO2000044110A1 (en) 2000-07-27
SE9900195D0 (sv) 1999-01-22
SE9900195L (sv) 2000-07-23
AU2337300A (en) 2000-08-07
SE515837C2 (sv) 2001-10-15

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